Liquidizer safety clutch

ABSTRACT

Liquidizer safety ejection clutch in which a resilient element operatively disposed between two axially engageable clutch elements yields under the combined weight of a jar and base of a two-piece container placed in working position to permit the clutch members to engage yet holds the clutch elements apart under the weight of the base alone to prevent operation of the exposed cutters when the jar is absent from the base.

United States Patent 72] Inventors Robert J..Emmons Manchester; MauriceP. Samuelian, West Hartford, both of Conn. [21] Appl. No, 850,182 [22]Filed Aug. 14, 1969 [45] Patented Oct. 12, 1971 [73] Assignee DynamicsCorporation of America New York, N.Y.

[54] LIQUIDIZER SAFETY CLUTCH 14 Claims, 5 Drawing Figs.

[52] US. Cl 146/68 A, 259/108, 192/89, 192/130 [51] Int. Cl ..B02c18/12, A47j 43/042 [50] Field of Search 146/68. 1

68; 259/108, DIG. 26; 192/129 A, 130, 89

[56] References Cited UNITED STATES PATENTS 2,356,004 8/1944 Price259/DIG. 26 2,930,596 3/1960 Waters 259/108 X 3,172,441 3/1965 Hartwiget al. 146/68 A Primary ExaminerWillie G. Abercrombie Attorney-Harbaughand Thomas ABSTRACT: Liquidizer safety ejection clutch in which aresilient element operatively disposed between two axially engageableclutch elements yields under the combined weight of a jar and base of atwo-piece container placed in working position to permit the clutchmembers to engage yet holds the clutch elements apart under the weightof the base alone to prevent operation of the exposed cutters when thejar is absent from the base.

LIQUIDIZER SAFETY CLUTCH RELATED APPLICATION Raymond-Set. No. 780,131,filed Nov. 29, 1968 now US. Pat. No. 3,540,234

BACKGROUND OF THE INVENTION Liquidizer containers for home use aregenerally provided with a vertical shaft in the bottom carrying highspeed cutters with convoluted walls tall enough thereabove to discouragea user from manually contacting the cutters during operation.

There are two types of containers, one a molded single unit jar with adownwardly opening cavity on the bottom concealing the disengageableclutch mechanism, and the other a twopiece container having a threadedconnection below the level of the cutters that are journaled in thebase. When disconnected the base and upper portions can be easilycleaned separately and different upper portions can be usedinterchangeably with the base portion if desired.

A further danger is created for the user with the two-piece container.Not only can the user reach into the container and contact the cuttersbut the base portion without the jar portion can be left on the powerunit with the clutch engaged and the beaters exposed as a result of anyone of a number of actions of the user. The user may unthread the jarportion while retaining the container on the power unit so that thepower unit can be gripped instead of the base portion in manuallyunthreading them; or, after unthreading the two parts the base portionis put back in drive position on the power unit for either temporary orprolonged storage without the user disconnecting the plug-in power cordfrom the house current.

In either event the speed control switch can be closed thoughtlessly,accidentally or prankishly, and the series wound motor which has hightorque, high-speed characteristics with a fast start can either flingthe base portion as an animated missile, or almost instantly whirl thecutters at such a speed that they-are not likely to be seen by a personreacting quickly to turn off the motor. Also intentional use of exposedcutters for any purpose is to be discouraged.

SUMMARY OF THE INVENTION In the present invention means are provided todisengage liquidizer clutch members when the protective presence of thejar portion of the container is absent and the base portion joumalingthe cutters is left in drive position with the cutters exposed. Aresilient element is employed capable of differentiating between theapplied weights of the base alone and the composite weight of the baseand jar secured together.

More particularly, resiliently extendable members disposed between themotor housing and the container, and carried by either one or both ofthem operate to displace the base and thereby disengage the clutchmembers when the jar portion of the container is absent. The extendablemembers are comounted as part of the clutching arrangement so that theirremoval dismantles at least one of the clutch elements. Also, they arenot adversely aflected if they too are submerged in water at the timethe cutters are being cleaned if mounted on the container.

The invention is further characterized by a two part liquidizercontainer having a light plastic base and preferably a jar portion madeof a ceramic, such as glass, for many advantageous reasons including itsweight factor and cleansability.

The invention further contemplates an added safety arrangement where notonly are the clutch members disengaged when the upper container portionis absent, but the electrical power circuit to the motor also may beinterrupted.

Another object of the invention for safety reasons is the provision of aremovable upper container portion which tapers upwardly to an openingtoo small for a person's hand to be received therethrough, but with awide opening at its lower extremity that provides easy access forthorough cleaning when removed from the base portion. Also the tapergreatly assists circulation and return of the contents to the center ofthe container when swirled up the sidewall by the cutter action.Furthermore, convolutions on the container wall can be greatly reducedin radial height to provide greater capacity in the container.

These being among the objects of the invention other and further objectsand advantages will appear from the following drawing and descriptionrelating thereto.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view partly cut awayat the top of the container of a liquidizer embodying the preferredembodiment of the invention;

FIG. 2 is an enlarged cross-sectional view showing the upper and lowerportions of the assembly of the twopiece container mounted in workingposition on a power unit with the clutch members in driving engagement;

FIG. 3 is a view similar to FIG. 2 showing the relationship and relativepositions of the base portion and power unit with the clutch membersdisengaged when the upper portion of the container is absent;

FIG. 4 is a view similar to FIG. 3 showing the con-joint operation witha safety cut-off modification providing dual safety; and

FIG. 5 is a schematic of the circuit portion involved with theembodiment of FIG. 4.

Referring now to FIG. 1 in further detail, a liquidizer is illustratedhaving a power unit 10 supporting a container 11 assembly of a basemember 12 removably receiving an upper or jar portion 14 closed at thetop by a closure 13.

The power unit includes a housing 16 supported on legs 18, with a serieswound motor 24 (FIG. 5) supported therein below a switch panel platform20 that has a collar 22 thereon. The wall 30 of the collar (FIGS. 2 and3) defines a cavity 28 having four angularly spaced resilient L-shapedinserts which serve as lugs 31 which receive the base in weight bearingand nonrotative relationship and the upper end of the vertical motorshaft 24 is joumaled in a bearing 26 located in the center of the bottomof the recess 28. The upper ends of the lugs 31 are beveled as at 33 toguide the base when lowered and it will be noted that without the base12 on it the lower end of the jar 14 can rest on the upper ends of thelugs within the rim of the wall 30 if it is stored alone at any time.

The base member 12 has a depending wall 32 whose outer surface 34 isprovided with eight vertical grooves to receive the lugs 31 verticallyin readily releasable nonrotative engagement in that both taper slightlyin a downward direction.

The wall 32 inwardly defines a cavity 36 below the cross wall 38 havinga flat surface 42 surrounding a bearing receiving opening 40therethrough that is coaxial with the shaft 24. The sidewall 44 of thecavity is cylindrical and is bordered by a circular groove 46 at the topthereof which receives the upper end of a helical compression spring 48.

The cutter assembly 50 received in the opening 40 includes a sleeve 52received through the opening 40 having a radial flange 54 adjacent itsupper end that rests on the upper face of the cross wall with a washergasket 56 therebetween. The lower end of the sleeve 52 receives aninverted cup member 62 thereon against the flat surface 42 and isterminally threaded to receive a washer 68 and nut 58 thereon forholding the sleeve and cup tightly in place in sealed relationship.

The cup member 62 is marginally provided with a flareflange 66 whosemarginal edge is located close to the cylindri cal wall 44, and acircular sleeve 69 telescopes between the flange 66 and cylindrical wall44. The circular sleeve has at the top thereof an inwardly directedflange 70 which supports the lower end of the spring 48 and engages theflange 66 for limited downward movement and the lower end of the sleeveis provided with an outwardly flared flange 72 which engages the bottomedge 74 of the base member 30 when the spring 48 is compressed. A lostmotion of a predetermined distance is thus provided for the sleevebetween engagement between flanges 66 and 70 and engagement betweenflange 72 and said bottom edge 74. The lower face of the flange 70 isdownwardly convex and smooth to avoid marring any surface finishescontacted by it.

Preferably, the body of the base member 12 is made of plastic materialfor the sake of lightness of weight and is not too heavy to preventelevating the base member by the spring 48 the lost motion distance asdetermined by the engagement of flanges 66 and 70. A plastic found to besuitable as an acrylonitrile-butadiene-styrene (ABS)-type polymet suchas the proprietary known as Cycolac.

A sintered metal sleeve bearing 60 is press-fitted in the sleeve 52 andjournals a driven shaft 76 which carries cutters 78 at the upper end ina conventional manner with a running washer seal 80 between the bearing60 and cutters 78. The lower end of the shaft 76 is shouldered as at 82for axial support of the shaft and adjacent ends of the drive and drivenshafts 24 and 76 are threaded as at 84 to receive cooperating clutchmembers 86 and 88, respectively, as more particularly described in saidRaymond application, which is incorporated by reference herein.

It is sufficient at this time to note that the driven element is a rigidmember having radiating spokes 90 offset their thickness enough thattheir drive faces are on true radii, and the drive element has circulararranged axially extending resilient teeth 92 interdigitating with thespokes 90. They are axially moved into and out of engagement with eachother within the distance of said lost motion determined flanges 70 and72 are explained.

Surrounding the cutter assembly 50 the base member is provided with acircular flange 94 preferably having coarse thread grooves 96 thereonmating with external thread lands 98 around the lower rim of the jar 14where the jar portion has its widest opening for cleaning purposes. Agasket 100 seals the joint when the threads are tightened.

The jar is preferably made of glass so that it can withstand beingwashed in a dish washer at high temperature. It thus has substantialweight, which when added to that of the base member will collapse thespring 48 to permit the drive and driven members to engage. The innerwall 102 of the jar tapers upwardly where it terminates in an inwardlydirected sharply tapered lower portion 106 of a flange 104 rounded to aflat upper surface 100 and defining an opening 108 approximately two andone-half inches in diameter which is too small for most hands to passthrough. A snap cap 110 of resilient material and any external designdesired has an axially directed depending flange 112 externally enlargedenough at its lower end to interfere with the rounded flange whereby itsnaps into place with a resilient engaging relationship. The tightnessinvolved is less than that which would enable lifting the jar by thecap.

Referring to FIGS. 4 and 5, as already mentioned cut-off switches havebeen used before that are actuated by the removal of the liquidizer jarfrom the power unit. Habits have been developed of stopping the motormerely by removing the jar without touching the stop switch. A circuitembodying this is shown in FIG. where the stop switch 110, motor 24 anda cut-off switch 112 are connected in series between two power lines Land L,. A push rod 114 actuated by the presence of a jar closes thecut-off switch which starts the motor if the stop switch is left closed.Light pressure is generally all that is required to close the cut-offswitch.

The present invention prevents dire results occurring from this habit. Astarting of the motor by closing the cut-off switch is prevented unlessthe two-piece jar is assembled and in place with the clutch membersengaged. Accordingly, the invention is adaptable for various power unitsbecause the spring 48 has to be collapsed to actuate the switch 112 nomatter how lightly the switch is biased, because, as shown in FIG. 3 inbroken lines, and FIG. 4 in solid lines, the push rod 114 for the switchis not actuated until the flange 66 is forced downwardly substantiallyits full distance.

Thus, whether a cut-off switch alone is used or none is used, the basemember 94 must be in place with the jar 14 on it before the cutterassembly is driven. Therefore, one supplements the other if both arepresent rather than one safety control operating in a way by-passing theother.

Moreover, the clutch members which have a wide leverage radius thatcould cause the most damage of available clutch members in flipping ordriving exposed cutters have been shown and described as representativeof other drives having smaller radii wherever the drive elements areengaged by rectilineal movement and include interdigitating members thatmight interfere momentarily. There is no engagement unless the jar ispresent along with the base.

What is claimed is:

l. A liquidizer comprising:

a power unit including a housing member,

a liquidizer container including a removable base member removablysupported in weight borne relationship on the housing member forvertical movement to and from the working position,

vertical drive and driven shafts journaled in said members in axialalignment with each other during said vertical movement,

axially engageable clutch elements carried by said shafts for engagementand disengagement with said movement,

means interengaging said members for urging disengagement of saidelements including reciprocable means carried by one of said members toengage the other of said members, and

resilient means carried by said one member urging said reciprocablemeans to move said clutch members out of engagement under the weight ofthe base alone.

2. The liquidizer as defined in claim 1 in which said clutch elementshave working radii greater than the distance of vertical movementrequired to move them from their working positions to a disengagedposition.

3. The liquidizer as defined in claim 1 in which one of said clutchelements has radially spaced extending flexible teeth intermeshing withthe other clutch element.

4. The liquidizer defined in claim 1 in which the drive shaft is thearmature of an electric motor, and

cut-off switch means in the electrical circuit of said motor opened bysaid resilient means as the clutch members are disengaged.

5. The liquidizer as defined in claim 1 in which one of said membershaving a cavity facing the other member,

said resilient means including a compression spring received inwardly ofthe wall of the cavity, and

said reciprocable means including a first sleeve interengaging the freeend of the spring and said other member,

a second sleeve carried by said one member retaining said spring andfirst sleeve in engagement with each other and permitting outwardmovement of the first sleeve at least the vertical distance of movementnecessary to disengage the clutch,

said spring being constructed and tensioned to extend said first sleevesaid distance under a weight load less than that of both of the jar andbase.

6. A liquidizer comprising a power unit carrying a rotary drive clutchelement at the top thereof,

a container including disengageable jar and base members,

a drive shaft journaled in said base carrying rotatable cutters at thetop thereof receivable in the jar,

a rotary driven clutch element at the bottom of the drive shaft axiallyengageable with said drive clutch element, support means on said powerunit receiving the jar and base in weight bearing relationship upon thepower unit in working position,

sleeve means reciprocably mounted on said base interengaging said baseand support means in weight bearing relationship,

resilient means interconnecting said base and sleeve means to urgedisengagement of the clutch elements under the weight of said basealone,

the weight of said jar and base collapsing said resilient means toengage said clutch elements.

7. The liquidizer defined in claim 6 in which said support meansincludes angularly spaced L-shaped lugs having lower portions engageableby said base and upstanding portions engageable by said jar when saidbase is absent.

8. The liquidizer defined in claim 6 in which said jar is made ofceramic, the base of plastic, and the sleeves of sheet metal.

9. A liquidizer including:

a tapered vertical jar member open at both ends and of a heightapproximately twice the diameter of the bottom opening with the area ofthe upper access opening being approximately one-half that of the bottomopening,

a base member including a bottom wall and an upstanding flangeencompassing the rim of said bottom opening in rotatably sealedrelation, and depending container support flange defining a cavity belowthe bottom wall,

a cutter assembly including a shaft joumaled in said bottom wall withits upper end extending above the level of said upstanding flange and aclutch member on its lower end disposed in said cavity,

a compression spring received inwardly of the wall of the cavity,

a first sleeve interengaging the free end of the spring and normallyextended outwardly by said spring at the other end beyond said supportflange,

a second sleeve carried by said base member retaining said spring andfirst sleeve in engagement with each other and pennitting outwardmovement of the first sleeve a predetermined distance,

the spring being constructed and tensioned to extend said first sleevesaid distance under a weight load less than that of both the jar andbase.

10. The liquidizer defined in claim 9 in which the area of the upperaccess opening is too small to receive human hands therethrough of asize most users have, and

said bottom opening having an area large enough to receive hands of mostusers for jar cleaning purposes.

11. The liquidizer defihed in claim 9 in which the diameter of the upperaccess opening is approximately two and one-half inches.

12. A liquidizer including:

a tapered vertical jar member open at both ends and of a heightapproximately twice the diameter of the bottom opening and having anupper access opening of an area approximately one-half that of thebottom opening;

a base member including a bottom wall and an upstanding flangeencompassing the rim of said bottom opening in rotatably sealedrelation, and a depending container support flange defining a cavitybelow the bottom wall;

a cutter assembly including a shaft joumaled in said bottom wall withits upper end extending above the level of said upstanding flange and amember on its lower end disposed in said cavity;

a removable cover for said access opening, said access opening being toosmall to receive human hands therethrough of a size most users have, and

resilient means within said support flange and extendable to carry theweight of said base member when detached from said jar member.

13. The container called for in claim 12 in which said jar member hasvertically extending convolutions which in cooperation with the taperedsidewall directs inwardly to the center of the container contentsswirling upwardly from the cutters along the sidewall.

14. The liquidizer defined in claim 12 in which the upper access openingis defined by an inwardly directed flange having rounded edges, asubstantially flat upper surface and a wall below it tapering to theupper internal wall of the jar,

the upper shape of the flange increasing the difficulty of a personshand entering the jar and the lower shape of the flange assisting theremoval of a hand if inserted in the jar.

1. A liquidizer comprising: a power unit including a housing member, aliquidizer container including a removable base member removablysupported in weight borne relationship on the housing member forvertical movement to and from the working position, vertical drive anddriven shafts journaled in said members in axial alignment with eachother during said vertical movement, axially engageable clutch elementscarried by said shafts for engagement and disengagement with saidmovement, means interengaging said members for urging disengagement ofsaid elements including reciprocable means carried by one of saidmembers to engage the other of said members, and resilient means carriedby said one member urging said reciprocable means to move said clutchmembers out of engagement under the weight of the base alone.
 2. Theliquidizer as defined in claim 1 in which said clutch elements haveworking radii greater than the distance of vertical movement required tomove them from their working positions to a disengaged position.
 3. Theliquidizer as defined in claim 1 in which one of said clutch elementshas radially spaced extending flexible teeth intermeshing with the otherclutch element.
 4. The liquidizer defined in claim 1 in which the driveshaft is the armature of an electric motor, and cut-off switch means inthe electrical circuit of said motor opened by said resilient means asthe clutch members are disengaged.
 5. The liquidizer as defined in claim1 in which one of said members having a cavity facing the other member,said resilient means including a compression spring received inwardly ofthe wall of the cavity, and said reciprocable means including a firstsleeve interengaging the free end of the spring and said other member, asecond sleeve carried by said one member retaining said spring and firstsleeve in engagement with each other and permitting outward movement ofthe first sleeve at least the vertical distance of movement necessary todisengage the clutch, said spring being constructed and tensioned toextend said firsT sleeve said distance under a weight load less thanthat of both of the jar and base.
 6. A liquidizer comprising a powerunit carrying a rotary drive clutch element at the top thereof, acontainer including disengageable jar and base members, a drive shaftjournaled in said base carrying rotatable cutters at the top thereofreceivable in the jar, a rotary driven clutch element at the bottom ofthe drive shaft axially engageable with said drive clutch element,support means on said power unit receiving the jar and base in weightbearing relationship upon the power unit in working position, sleevemeans reciprocably mounted on said base interengaging said base andsupport means in weight bearing relationship, resilient meansinterconnecting said base and sleeve means to urge disengagement of theclutch elements under the weight of said base alone, the weight of saidjar and base collapsing said resilient means to engage said clutchelements.
 7. The liquidizer defined in claim 6 in which said supportmeans includes angularly spaced L-shaped lugs having lower portionsengageable by said base and upstanding portions engageable by said jarwhen said base is absent.
 8. The liquidizer defined in claim 6 in whichsaid jar is made of ceramic, the base of plastic, and the sleeves ofsheet metal.
 9. A liquidizer including: a tapered vertical jar memberopen at both ends and of a height approximately twice the diameter ofthe bottom opening with the area of the upper access opening beingapproximately one-half that of the bottom opening, a base memberincluding a bottom wall and an upstanding flange encompassing the rim ofsaid bottom opening in rotatably sealed relation, and dependingcontainer support flange defining a cavity below the bottom wall, acutter assembly including a shaft journaled in said bottom wall with itsupper end extending above the level of said upstanding flange and aclutch member on its lower end disposed in said cavity, a compressionspring received inwardly of the wall of the cavity, a first sleeveinterengaging the free end of the spring and normally extended outwardlyby said spring at the other end beyond said support flange, a secondsleeve carried by said base member retaining said spring and firstsleeve in engagement with each other and permitting outward movement ofthe first sleeve a predetermined distance, the spring being constructedand tensioned to extend said first sleeve said distance under a weightload less than that of both the jar and base.
 10. The liquidizer definedin claim 9 in which the area of the upper access opening is too small toreceive human hands therethrough of a size most users have, and saidbottom opening having an area large enough to receive hands of mostusers for jar cleaning purposes.
 11. The liquidizer defined in claim 9in which the diameter of the upper access opening is approximately twoand one-half inches.
 12. A liquidizer including: a tapered vertical jarmember open at both ends and of a height approximately twice thediameter of the bottom opening and having an upper access opening of anarea approximately one-half that of the bottom opening; a base memberincluding a bottom wall and an upstanding flange encompassing the rim ofsaid bottom opening in rotatably sealed relation, and a dependingcontainer support flange defining a cavity below the bottom wall; acutter assembly including a shaft journaled in said bottom wall with itsupper end extending above the level of said upstanding flange and amember on its lower end disposed in said cavity; a removable cover forsaid access opening, said access opening being too small to receivehuman hands therethrough of a size most users have, and resilient meanswithin said support flange and extendable to carry the weight of saidbase member when detached from said jar member.
 13. The container calledfor in claim 12 in which said jar member has vertically extendingconvolutions which in cooperation with the tapered sidewall directsinwardly to the center of the container contents swirling upwardly fromthe cutters along the sidewall.
 14. The liquidizer defined in claim 12in which the upper access opening is defined by an inwardly directedflange having rounded edges, a substantially flat upper surface and awall below it tapering to the upper internal wall of the jar, the uppershape of the flange increasing the difficulty of a person''s handentering the jar and the lower shape of the flange assisting the removalof a hand if inserted in the jar.